Problem: $-\dfrac{9}{5} - \dfrac{6}{10} = {?}$
Explanation: $ = - {\dfrac{9 \times 2}{5 \times 2}} - {\dfrac{6 \times 1}{10 \times 1}} $ $ = - {\dfrac{18}{10}} - {\dfrac{6}{10}} $ $ = - \dfrac{{18} - {6}}{10} $ $ = -\dfrac{24}{10}$